The T-50 is currently undergoing flight tests that have so far been successful, Bondarev said. Previous reports stated that the aircraft would enter into service in 2016.

“Under the program, we will finish testing next year and will begin to receive the T-50 jets in 2017," Bondarev said.
According to Bondarev, the aircraft fully meets the requirements.

The T-50 prototype aircraft is designed by the Russian Sukhoi aircraft manufacturer for the PAK FA, a fifth-generation fighter program of the Russian Air Force.

The fighter jet is expected to become the first operational stealth aircraft for the Russian Air Force and will incorporate advanced avionics and all-digital flight systems.

The aircraft is a stealthy, single-seat, twin-engine jet fighter, and will be the first operational aircraft in Russian service to use stealth technology. It is a multirole fighter designed for the air superiority and attack roles. The fighter is planned to have supercruise, stealth, supermaneuverability, and advanced avionics to overcome the prior generation of fighter aircraft as well as ground and maritime defences. The PAK FA is intended to be the successor to the MiG-29 and Su-27 in the Russian Air Force and serve as the basis for the Fifth Generation Fighter Aircraft (FGFA) being co-developed by Sukhoi and Hindustan Aeronautics Limited (HAL) for the Indian Air Force. The T-50 prototype first flew on 29 January 2010 and the first production aircraft is slated for delivery to the Russian Air Force starting in late 2016 or early 2017. The prototypes and initial production batch will be delivered with a highly upgraded variant of the AL-31F used by the Su-27 family as interim engines while a new clean-sheet design powerplant is currently under development.

The Russian Air Force is expected to procure more than 150 PAK FA aircraft, the first of which is slated to be delivered in 2016. India plans on acquiring modified PAK FA as a part of its Fifth Generation Fighter Aircraft (FGFA) program. It originally planned on buying 166 single-seat and 44 two-seat variants, but this has been reduced to 130-145 single-seat aircraft and the requirement for 45-50 twin-seat fighters has been dropped by 2014. The Russian Defence Ministry plan on purchasing the first 10 evaluation example aircraft after 2012 and then 60 production standard aircraft after 2016.

In December 2014, the Russian Air Force planned to receive 55 fighters by 2020. But Yuri Borisov, Russia's deputy minister of defence for armaments stated in March 2015 that the Air Force will slow PAK FA production and reduce its initial order to 12 jets due to the nation's deteriorating economy. Due to the aircraft's complexity and rising costs, the Russian Air Force will retain large fleets of fourth-generation Sukhoi Su-27 and Su-35S